Peritoneal carcinomatosis (PC) and malignant pleural effusions (MPE) are two common complications of cancers metastatic to the respective body cavities. A PC diagnosis indicates metastasis to the tissue lining the abdominal cavity and is most common in patients with gastrointestinal and gynecological cancers. It is often accompanied by ascites, an accumulation of serous fluid in the abdomen. MPE presents as the accumulation of fluid in the space between the lungs and chest wall. It is a common terminal event in patients diagnosed with breast cancer, lung cancer, lymphoma, and mesothelial cancers, and less commonly, in a wide variety of other epithelial cancers. Due to the aggressive nature of cavitary tumors, the outcome of current treatments for both PC and MPE remains bleak. Although PC and MPE are characteristically affected by different sets of primary tumors (lung/breast/mesothelioma for MPE and gynecologic/gastrointestinal for PC), their environments share common cytokines and cellular components. Owing to the unique cytokine and chemokine content, this environment promotes aggressive tumor behavior and paradoxically both recruits and suppresses central memory and effector memory T cells. The cellular and secretomic complexity of the cavitary tumor environment renders most currently available therapeutics ineffective but also invites approaches that leverage the robust T-cell infiltrate while addressing the causes of local suppression of anti-tumor immunity. Interactions between the heterogeneous components of the tumor environment are an area of active research. We highlight the roles of the immune cell infiltrate, stromal cells, and tumor cells, and the soluble products that they secrete into their environment. A more comprehensive understanding of the cavitary tumor environment can be expected to lead to better immunotherapeutic approaches to these devastating conditions.
腹膜癌病（PC）与恶性胸腔积液（MPE）是癌症转移至相应体腔的两种常见并发症。PC诊断表明癌细胞已转移至腹腔内壁组织，最常见于胃肠道癌和妇科癌症患者，常伴随腹腔内浆液性积液（腹水）。MPE表现为肺与胸壁之间腔隙的液体积聚，是乳腺癌、肺癌、淋巴瘤及间皮瘤患者常见的终末期表现，亦可见于多种其他上皮源性肿瘤但较为少见。由于腔隙性肿瘤的侵袭性特征，目前针对PC与MPE的治疗效果均不理想。 尽管PC与MPE通常受不同原发肿瘤影响（MPE常见于肺/乳腺/间皮瘤，PC多见于妇科/胃肠道肿瘤），但其微环境具有相似的细胞因子与细胞组分。这种独特的细胞因子和趋化因子构成，既促进肿瘤侵袭行为，又矛盾地同时募集并抑制中央记忆性T细胞与效应记忆性T细胞。腔隙肿瘤微环境的细胞与分泌组复杂性导致现有多数疗法难以奏效，同时也为治疗策略提供了新思路：在利用显著T细胞浸润的同时，需解决局部抗肿瘤免疫受抑制的机制。 肿瘤微环境中异质性组分间的相互作用是当前研究热点。本文重点探讨免疫细胞浸润、基质细胞、肿瘤细胞及其分泌至微环境中的可溶性因子的作用机制。对腔隙肿瘤微环境更全面的理解，有望为这些严重病症开发更有效的免疫治疗策略。
肿瘤(癌症)患者之家